diff --git a/asio_compatibility.hpp b/asio_compatibility.hpp
index 1e6648d..a9abd7c 100644
--- a/asio_compatibility.hpp
+++ b/asio_compatibility.hpp
@@ -50,7 +50,7 @@ namespace SimpleWeb {
   void async_resolve(asio::ip::tcp::resolver &resolver, const std::pair<std::string, std::string> &host_port, handler_type &&handler) {
     resolver.async_resolve(host_port.first, host_port.second, std::forward<handler_type>(handler));
   }
-  asio::executor_work_guard<io_context::executor_type> make_work_guard(io_context &context) {
+  inline asio::executor_work_guard<io_context::executor_type> make_work_guard(io_context &context) {
     return asio::make_work_guard(context);
   }
 #else
@@ -76,7 +76,7 @@ namespace SimpleWeb {
   void async_resolve(asio::ip::tcp::resolver &resolver, const std::pair<std::string, std::string> &host_port, handler_type &&handler) {
     resolver.async_resolve(asio::ip::tcp::resolver::query(host_port.first, host_port.second), std::forward<handler_type>(handler));
   }
-  io_context::work make_work_guard(io_context &context) {
+  inline io_context::work make_work_guard(io_context &context) {
     return io_context::work(context);
   }
 #endif